The invention relates to an attachment of an industrial vehicle, including forklift trucks, that manipulates or handles a load under monitored operation conditions.
Industrial vehicles, including forklift trucks, may be fitted with a large variety of attachments, for example, which may be mounted on an end of the vehicle. These attachments may be used to lift, carry, transport or otherwise manipulate a load or object which requires some level of dexterity and care so that the load is not damaged or inadvertently dropped. Forks, clamps, buckets, shovels and any number of other attachments have been designed for handling a load. Furthermore, the attachments may be fitted with hydraulic devices that enable different side-shift, tilt, rotate and/or lift operations. This wide variety of attachments and attachment operations can create a significant transfer of load moment and affect vehicle stability, particularly when the load is at an elevated position.
Conventional industrial vehicles may often be required to lift or handle a load that is located a certain distance away from the vehicle. For example a forklift truck may include forks to pick up the load. Fork spacers may be inserted on the forks to extend the attachment reach when it is not convenient to move the vehicle closer to the load. The fork spacers increase the total length of the vehicle and can negatively affect the maneuverability or turning radius of the vehicle. Different amounts of attachment reach may be desired that may require different length fork spacers. The installation time required to attach different length fork spacers reduces the time efficiency of the lift truck.
A “double bite” technique may be used when handling a remote load. The “double bite” technique is an operation where a forklift truck lifts a load with an outer portion of the forks, traverses backward a distance, sets the load down on the ground, and then moves forward and fully engages the load. A load should be fully engaged during transportation and handling. Double biting a load can cause damage to a load, place stress on the forks, and result in operating inefficiencies.
In some industrial vehicles, a pantograph mechanism may be provided that enables a load handling device to be extended and retracted. As the pantograph mechanism is extended, a moment associated with the load weight increases and may destabilize the vehicle.
Conventional industrial vehicles including travel speed restrictions determine a maximum allowable travel speed as a function of lift height or other operating parameters. Travel speed may be varied in steps according to threshold lift height values, or the travel speed may be varied linearly as a function of lift height. These travel speed restrictions result in limiting vehicle performance to a worst case vehicle stability condition, and therefore reduce operational efficiencies in many applications.
Conventional industrial vehicles may include lift height restrictions, for example, to reduce a risk of damaging the mast or load inside of a warehouse facility. These systems also reduce operational efficiencies.
The present invention addresses these and other problems associated with the prior art.